Polycarbonate resins are thermoplastic resins having an excellent impact resistance, heat resistance and the like that are widely used in areas such as electrical, electronic, OA, mechanical and automotive applications. In addition to the excellent performance exhibited by polycarbonate resins, a material having excellent flame retardance is being sought to satisfy the safety demands encountered in the electrical, electronic and OA fields. Therefore, many methods in which an organic bromine compound or an inorganic compound represented by phosphorus type compounds or metal oxides is added to improve the flame retardance of polycarbonate resins have been proposed and used.
However, the generation of a gas containing a halogen upon combustion is a concern when a halogen type compound such as an organic bromine compound is formulated, and desired in the market is a flame retarding agent that does not contain chlorine, bromine and the like. Numerous resin compositions obtained by adding a phosphorus type flame retarding agent typified by phosphate esters have been proposed as halogen free materials for flame retardant polycarbonate resins. To avoid the problems of adhesion to metal molds and metal mold pollution when molding the composition, for example, condensation type phosphate esters derived from resorcin are used in particularly numerous cases.